I wouldn't worry too much about the baking soda or borax for now--the Borax is used to raise pH, which usually doesn't need to be done with a SWCG, unless the initial pH is too low. Same goes for the baking soda--no reason to add it unless your TA is way, way low.

I agree with AnnaK that you'll need salt and CYA, but you really need test results from your fill water before you spend a lot on baking soda and Borax--not every pool needs those.

Janet